Water always wins

We get a lot of junk mail through the door, but I always have a look through the Valley Life magazine*, as between the small ads, recipes, and gardening tips there is usually one article featuring of old photographs of the area. Many of the scenes are still recognisable and I love trying to work out where the photographer was standing, which buildings are still there, which have been demolished, and so on.

This month’s issue delves into the fascinating world of civil engineering and Victorian architecture and describes how Widdop reservoir supplies Halifax with fresh water. The reservoir was built in the 1870s and holds 640,511,000 gallons of water, but lies high above Hebden Bridge, with nearly 8 miles (as the crow flies) of hills and valleys to cross before reaching the town. Work was supervised by the excellently-named John F La Trobe Bateman (FRSE FRS MICE FRGS FGS FSA and President of the Institution of Civil Engineers in Britain 1878-9), who seems to be responsible for constructing much of the country’s water supply infrastructure at the time.

Widdop valve house

A number of valleys had to be crossed en route to the city – in some places, aqueducts were built, but elsewhere an ingenious device called an inverted syphon was employed.

Inverted syphon

The principle is similar to the u-bend under a sink, and as we can see here, fairly simple to set up (that site gives me flashbacks to Chemical Engineering classes. So glad I didn’t spend the next three years calculating flows).

One of the syphons lies between Hollins Hall and Pecket Well, but the land on the other side of the valley is higher, so a tunnel had to be dug through the hillside. The Castle Carr tunnel is 2550 yards long and has three ventilation shafts, the deepest of which is 476 yards. They can be clearly seen on the OS 1:25,000 maps if you have one (if not Bing will be able to help you, just change the view to Ordnance Survey). The shafts are listed by Historic England, as they show “Good examples of stonemasons work on top of the moors in an isolated location”.

Pecket Well ventilation shaft

I’d noticed these shafts a few weeks ago when I was running up there, but couldn’t quite work out what they were. It’s too far from the railway line, so unlikely to be a train tunnel; I assumed it was a mine of some sort. It’s not a good place for mining though, as apparently the rock is so hard that the explosive charges were just blasted out of the drill holes, having no effect on the rock at all.

The tunnel ends at the Castle Carr estate, a country retreat which the article says contains the highest gravity-fed water feature in the UK (though the fountains at Chatsworth and Stanway are higher. Perhaps they meant height above sea level. At 300 metres it’s pretty hard to beat). I’d never heard of this place before and it’s not surprising – it has fallen into ruin and is only open to the public one day a year. This report makes it sound like it is really worth visiting, so I’ll try and make the trip next month.

Maybe I’ll get round to writing another post about it!

[*] No hyperlink, as the address they give, http://www.facebook.com/Valley-Life-magazine redirects to http://www.facebook.com/valleylifemagazine, which is an Italian lifestyle magazine. Not sure what’s going on there. I’m not on Facebook, so maybe that kind of thing happens all the time. Who knows?

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Mapped: The whole of underground Manchester

I’ve always been fascinated by the hidden tunnels and chambers beneath our streets and Manchester has more than its fair share. I bought the book Underground Manchester a few years ago and thought it pretty comprehensively covered this secret world most of us know nothing about. However, a recent article in the Manchester Evening News shows that the city has many more stories to tell.

Mancunian enthusiast Mark Crossfield has spent the last few years putting together Hidden Manchester – a site dedicated to his love of the Manchester Underground. The MEN article contains a few good examples, but I thoroughly recommend a look at the site as it is packed with information.

Cartographically, it is not very exciting – just a push-pin overlay on a satellite basemap – but all the features have popup information with links for further reading. There isn’t any attribution on the basemap (I think it’s Google) and it doesn’t seem to be possible to switch to a vector map instead of imagery or turn on a street labelling layer either, but this map is definitely more about content than presentation. The sources page is full of interesting links and is probably worth the price of admission alone. There is certainly enough here to keep me quiet for some time.

 

Ships, Clocks & Stars

Despite the fact that my family is from London, and I was born there, I’ve never been to Greenwich. This means I’ve never seen the Royal Observatory or the Greenwich meridian, even though it is, quite literally, the centre of the world. Kind of.

Anyway, last weekend was a good time to put this right, as the Royal Museums Greenwich are holding an exhibition to celebrate the 300th anniversary of the Longitude Act. If you haven’t been already, I strongly recommend a visit before the exhibition ends on 4th January 2015. It’s the first time that all five of John Harrison’s timepieces are on public display together.

Sailing in the 18th century was a hazardous business, and poor navigation often resulted in longer journeys or even shipwreck, as with the Scilly disaster of 1707. The main difficulty was determining a ship’s position while at sea; establishing latitude was fairly straightforward, by measuring the angle of the sun over the horizon at midday, but longitude proved more of a challenge. The most common method was to use dead reckoning – basically to follow a bearing and assume that you haven’t been blown off course by the wind or tides.

The government decided to start a competition to solve the problem and passed the Longitude Act of 1714, which established the Board of Longitude, who would award a prize of up to £20,000 to whoever could come up with a method of determining longitude at sea.

(Interestingly, this article suggests that the Longitude Act was just a distraction to postpone actually doing something about the appalling conditions on board ship at that time.)

Five methods emerged as contenders, most of which used time to determine longitude. Given that the sun moves through 360° every 24 hours, that’s 15° every hour. So, if you are 15° W of Greenwich, it will be midday one hour later. The local time can be determined by seeing when the sun is at its apex (i.e. midday), so it follows that if you know the local time and the time at Greenwich, you can work out how many degrees of longitude you have travelled. So, how do we know the time in Greenwich when we have been at sea for weeks or months on end? Clocks of that period were unreliable and could not keep time during a long voyage.

Signalling

Probably the least plausible method was to set up an array of signalling stations that would send up a rocket at regular intervals, say every hour. The idea was that sailors would hear the signal and recalibrate their onboard timepieces. Also, the time difference between seeing and hearing the flare would allow the distance from the signal to be calculated.

The problem with this method is the difficulty of maintaining the position of ships at sea, making sure the signals were released at the right time, and the reliability of ordnance. Would the rocket reach the right height, or explode too early?

Magnetism

It was known at the time that the Earth’s magnetic field varied and that there was a difference between magnetic north (as shown by a compass) and true north (as shown by the Sun and stars). Some people thought that if the all the magnetic fields across the globe could be mapped, then they could be used to determine a ship’s position. This chart by Edmond Halley is an attempt at plotting these fields:

Sea chart of magnetic variations

A new and correct sea chart of the whole world showing the variations of the compass as they were found in the year 1700
© National Maritime Museum, Greenwich, London

Unfortunately, the Earth’s magnetic field changes over time and has too many local variations for this method to be of any use.

Jupiter’s Moons

The idea of using lunar or solar eclipses to determine time had been considered before, but these events were too infrequent to be of much use. However, when Galileo discovered in 1610 that Jupiter had four moons that disappeared behind the planet and reappeared at regular intervals, he realised that this method had some potential. He attempted to persuade first the Spanish, then the Dutch government to produce telescopes and train navigators to make the observations, but he was unsuccessful. Even one hundred years later, improved technology could not make instruments accurate enough to view a small object like Jupiter from the deck of a moving ship. This method did prove to be very effective though for establishing longitude on land and was used well into the 18th century.

Lunar Distances

If Jupiter’s moons were difficult to observe, a method requiring observations of our own moon should have been much easier. The idea was that an angle could be measured between the Moon and a star, for example the pole star, giving a ‘lunar distance’. After consulting an almanac of distances – and also altitudes of the Moon and stars – for various places around the globe, the local time should be easily determined. However, the Moon’s motions are very complex and constructing such a table proved very difficult.

Timekeepers

The most accurate clocks of the period incorporated pendulums, which were unable to function properly on a moving ship. Watches and smaller timepieces were too susceptible to heat and humidity to remain accurate over long periods of time. A young clockmaker from Lincolnshire, John Harrison, had started to experiment with using wooden components, which required no oil, yet were almost frictionless. Over the next few decades, he constructed a series of timepieces (H1-5, on display as the centrepiece of the exhibition), continually making improvements, but never quite doing enough to please either himself or the Board of Longitude. The clocks performed well over a number of sea trials, with, for example, Captain Cook referring to his ‘trusty friend’ and ‘never-failing guide’. Eventually, Harrison petitioned the Prime Minister, and after a debate in parliament, he was awarded  £8750.

John Harrison's H1

Three-quarter view of Harrison’s marine timekeeper H1
© National Maritime Museum, Greenwich, London, Ministry of Defence Art Collection

It’s clear that the Board were reluctant to award any of the prize to Harrison and continued to champion the lunar distance method, as favoured by Nevil Maskelyne, the Astronomer Royal. They kept asking for Harrison’s timepieces to be sent on more sea trials and often discounted the trials that had taken place, claiming they were ‘unofficial’. The Board was stuffed with parliamentarians, Fellows of the Royal Society, and other members of the establishment and they weren’t about to give to prize away to some chippy northener. (This article sheds a little more light on Maskelyne’s role in the affair.)

I don’t think the exhibition made enough of Harrison’s struggles against the establishment, but nevertheless, it is fascinating and packed with information. There is so much more to see, as the institution is actually four museums on one site – hopefully I’ll have time to go and visit the rest of it before too long.

Geography is awesome

I love living in the Pennines, the landscape really is stunning. Here in Hebden Bridge, beautiful sandstone mills and houses cling to the steep valley sides, while narrow, twisty roads wind impossibly between them. The valley does present a slight obstacle if, like me, you’re into cycling or running though. Basically, you have a choice between going along the canal, which is a bit dull, taking your chances on the main road with all the lorries and buses, or a brutal ascent up the valley side. If you take the third option, however, you are rewarded with fresh air, amazing views, and an excellent reminder of how the forces of nature have carved out the landscape over thousands of years.

I went for a run to Stoodley Pike this afternoon and on the return leg, saw this beautiful view (the way out was much less pleasant, running uphill into a blinding sun, but maybe that makes it more worthwhile).

Kilnshaw Lane

I love how as you travel up the valley, you can see two kinds of erosion – here to the right, above the green barn, is the side of a classic U-shaped glacial valley. During the last ice age, millions of tons of ice flowed along here, slowly grinding away at the base rock. When the ice melted, a broad,  flat valley was left behind. A slightly better defined example is shown below.

Glacial valley

You want more detail? Of course, this page should tell you everything you need to know about glaciers.

Further over to the left, the valley is cut again by fluvial erosion, as the River Calder wears a V-shaped scar into the landscape. It’s not very clear in the image above, so here is a better view, taken from Hell Hole rocks, below Heptonstall.

Calder Valley

I’ll leave The British Geographer to explain the process in detail, but you can clearly see how the straight valley sides contrast with the curved side above.

I never tire of the views up here, and think that seeing the results of these two processes next to each other always reminds me how awesome Geography is.

The Apple Dog

Entering the US is never easy, especially with children in tow. I came through Dulles airport recently with my family and had the usual hour waiting in line to get through passport control. We picked up our bags, then just as we were heading through customs, with the exit in sight, I heard a voice behind me.

“Excuse me sir, do you have an apple in your bag?”

I turned round to see a uniformed woman with a very excited dog by her side. After a brief moment of panic, I remembered – there were two apples in there earlier in the day, but luckily the kids had eaten them during the flight. I explained and let her check my bag and we were free to go. Hopefully the dog wasn’t too disappointed, but I told him he’d done well anyway. The handler told me he could identify 60 types of fruit and vegetables, but didn’t elaborate on how he could tell her which one he’d found – one can only imagine. It all happened behind me, so I’m not sure what he did on this occasion.

I knew that detection dogs could be used for drugs, explosives, and people, but I didn’t know they could do fruit and veg too. It’s all very impressive, and I’m glad that man’s best friend can help us out in so many ways – for more examples, see here (can require login, cached version here) and here.

When is a map not a map?

I took a trip to Sheffield today, mostly to see an old friend, but also to visit Inside the Circle of Fire: A Sheffield Sound Map at the Millennium Gallery. This exhibition was put together by Chris Watson, a founder member of the legendary Cabaret Voltaire, but with a subsequent career as a sound recordist, specialising in natural history. I was intrigued by the idea of a sound map, and was interested to see how sounds could be placed in a geographical context. As the exhibition blurb says,

In this ambitious new exhibition, Chris will transform the Millennium Gallery into an immersive ‘sound map’ of Sheffield, charting its boundaries on the edge of the Peak and travelling its waterways to the bustling heart of the city.

Unfortunately, I must have misunderstood, as the exhibition is not a map in any sense that I’m aware of. It was interesting, and I would have stayed to listen to the whole work if I didn’t have a bored child with me who wasn’t having any of it (though he did raise a smile when the terraces of Bramall Lane started to reverberate to the sound of Seven Nation Army). The gallery was dimly lit, with projections showing black and white images of the city (though with no explanation or location). In the centre of the room were four couches set facing each other; other benches were placed along the walls, and cushions were on the floor, to give different perspectives of the work.

While we were there, we heard church bells, birdsong, a woodpecker tapping at a tree, various industrial sounds, football chants, etc., but they were just sounds, coming from nowhere (or from everywhere, depending on whereabouts in the gallery you sat). There was no sense of where these sounds were located, where they belonged. I know I’m probably being a square who’s trying to find meaning and force an explanation onto something, but that’s not the point. I’m quite happy to enjoy this piece as a sound installation, or a sound collage, or a soundscape (as the guy lying on the couch with his eyes closed clearly was. Unless he was asleep), but it’s not a map. To me a map shows the relationship between items, rather than randomly serving them up without explanation.

That said, I would love to see it again, or maybe get a podcast and while away those long train journeys listening to “an affectionate portrait of a city that the 19th century writer John Ruskin called ‘a dirty picture in a golden frame.’“.

Konichiwa Manchester!

I was passing through the Japanese department of Manchester University at the weekend (don’t ask why, it’s a long story), when I saw this entertaining poster on someone’s office door. It shows the city centre and selected landmarks, with a lot of cartographic licence in play – whole streets and junctions are missing and the trams have just been dumped randomly between buildings. I don’t think it is intended for navigation though…

Manchester Japanese

Now, I don’t speak any Japanese, but a few minutes on Google translate told me that the word in blue is ‘Manchester’. The second word is probably ‘music’, as it matches the first word below Music Box and Rockworld. Any suggestions as to the last word of the title, please feel free to comment below.

Even if I don’t know the full title of the map, there’s no mistaking the theme – the legend lists twenty music venues around the city and many Mancunian musicians can be seen wandering the streets. The monobrowed Gallagher brothers loom out of the lower left corner, a bequiffed Morrissey is to the right, and the sainted Anthony H. Wilson stands next to the old Granada Studios. Yes, I know that he and many of the people shown here are actually from Salford, but they’re on the other side of the river today.

Looking a bit closer, there are plenty more characters, though I don’t recognise them all. Perhaps some are just random bystanders – let me know if I’ve missed anyone.

Manchester Mondays

Doing some freaky dancing on the roof of GMEX is Bez from the Happy Mondays, while Shaun Ryder gets up to no good with some pigeons nearby. Ian Curtis stands on Deansgate, a very simian-looking Ian Brown is coming round the corner, and I think that’s John Robb outside the Hacienda.

Manchester BeeGees

Further south, the Bee Gees are dancing down Oxford Road, while the Cornerhouse is showing (what else?) 24 Hour Party People. I’m not sure about the guy on the corner – is he a lost raver? Answers on a postcard.

Manchester Smith Hucknall

Over near Canal Street (where Pride seems to be in full swing), Mark E. Smith is having a good shout at a taxi, and Mick Hucknall is standing in Piccadilly Gardens.

Manchester Small Evans

Waiting for a bus at the top of Deansgate is Heather Small, and that might be Chris Evans behind triangle, though it could be anyone to be honest.

Manchester Badly Drawn Hook

Lurking near Piccadilly Records is Badly Drawn Boy, and that must be Peter Hook outside the Dry Bar. It doesn’t look anything like him, but that’s his stance alright.

It’s hard to put a date on this map, but there a plenty of clues. The copyright notice on the right hand side names Creative Lynx, which ceased to exist in June 2012, GMEX was renamed in 2007, and the Hacienda was demolished in 2002. Granada Studios and the BBC only closed this year, as they moved to Media City, and lastly Tony Wilson became the late Tony Wilson in 2007.

I think the best guess is closer to 2002, when 24 Hour Party People was likely to be on in the cinema, though given how much popular culture Manchester has to celebrate, it’s probably on there all the time.